Drives for parasols having an upper mast part which may be raised and lowered telescopically are known for example from DE 2 353 967 A. There it is proposed that the telescopic part be driven by means of an upper articulation ring by way of a circulating toothed belt. According to DE 2 353 967 A, the toothed belt is to emerge through an opening in the mast at the drive gear and be attached to the telescopic part again at the upper circulating gear. The disadvantage here is that the toothed belt, which is open, can easily be damaged where it is outside the mast. Furthermore, the fact that it could not satisfy aesthetic demands has proved to be a drawback. In addition, the apertures in the mast wall have the effect of making the mast as a whole substantially less strong.
U.S. Pat. No. 4,424,824 A proposes, instead of a circulating member for actuating the telescopic part, using an angled gear for a spindle with a spindle nut in the telescopic part. Admittedly, this does replace the toothed belt and the aperture in the mast for the drive crank is small enough for the loss of strength in the mast no longer to be important; however, the solution proposed in U.S. Pat. No. 4,424,824 A is very disadvantageous in another respect, namely that an angled gear is required, and the crank has to be turned many times to achieve the required stroke length to open and close the parasol.